Chair back adjusting means



Sept. 9, 1947. 'J. WHITE CHAIR BACK ADJUST;NG MEANS Filed March '27; 1945 {Nl/ENTOR. 2f zi y OO ll www..

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IL. 17a 1a 19 Patented Sept. 9, 1947 UNITED' STATES PATENT GFFICE CHAIR BACK ADJUSTING MEANS Joseph White, Jackson Heights, N. Y. Application March Z7, 1945, Serial No. 585,108

2 Claims.

This invention relates to adjustable stop hinges and to articles associated therewith.

One object of the invention is to provide improved means for a positive stop action adjustable at a point remote from the hinge and without relying upon the uncertain action of frictional clamps or spring catches.

Another object of the invention is the provision of a hinge having adjustable stop means located along and preferably largely concealed within a coasting wall or frame member, and beingdesirably reenforced by thev latter.

Another object of the invention is to furnish `a device of the character described including cam means in improved association with adjustable stop elements whereby swinging movement is stopped in one directionbut is free. to occur in an opposite direction.

Another object of the invention is to construct a device of the type mentioned having improved adjustable stop hinge means including a cam and settable means for locking a bar at a given angle and preventing relative movement thereof in either direction.

v More particularly, the invention may be embodied with substantial advantage in chairs having swingable backs for sitting and reclining positions. Heretofore such chairs have been provided with adjustable stops not associated with the hinges. These stops generally consisted of thumbscrews frictionally bearing on a rod to prevent longitudinal movement thereof. Such thumbscrews require a very powerful grip for tightening, and `often the rod against which screw bears becomes chewed up andthe stop yields If the thumbscrew is loosened, the back may accidentally drop all the way rearward. A

and slips.

easily made and controlled at all times, and this can be accomplished even by the invalid seated in the chair. sit up straight for a short while, but with the back of the chair locked, he has no support unless he releases the adjustment. With the present invention such frequent changes of adjustment are not necessary, but when an adjustment is desired it can be made very quickly with only one turn or less of a conveniently located knob.

Generally described, the invention provides a hinge orjournal including a relatively Xed cam, and a follower rod for the cam slidable in a bore or tubel of one of the parts interconnected by the hinge, the range of reciprocation or other movement of the follower rod being limited by an adjustable stop which may form a cap or plug Frequently the invalid desires to Z having, for instance, a running thread engagement with the part in which the follower rod is sleeved. The follower rod may be as long as the part will permit, for remote control of the stop hinge, and the follower rod may act in compression, with the encasing part concealing and reenforcing it against bending strains which occur due to its thinness. As thev distance between the cooperating cam surface and the cap increases, an idler is free and may be loose, but as soon as hinging movement decreases that distance, the rod is placed under compression and stops the swinging movement in one direction. However, angular movement may freely occur in the opposite direction, and especially in a reclining chair; the back may thus be freely swung to upright position by a spring or other yielding force. If it bedesired to modify the device to afford a positive stop against hinging movements in both directions, then the follower rod is positively connected to the cap or stop and to the cam whereby the rod acts in compression and in tension for respective swinging movements in opposite directions. When under tension, certain deections are caused in the rod which may render it desirable to provide a link at the point where the rod engages the cam.

Other objects and advantages of the invention will become `apparent as the speciiicationv proceeds. p

With the aforesaid objects in view, the invention comprises the novel features, combinations and arrangements of parts hereinafter described in their preferred embodiments, pointed out in the subjoined claims, and illustrated in the annexed drawing, wherein like parts are designated by the same reference characters throughout the several views. v

In the drawing:

Figure 1 is a fragmentary view in elevation with parts removedland other parts in section showing an adjustable reclining chair embodying the invention. v

Fig. 2 is an enlarged sectional view taken on line 2--2`of Fig. 1.

Fig. 3 is a vertical sectional view through the hinge and back of the chair when said back is in vertical position.

Fig. 4 is a sectional view of a modification whereby the cam follower rod is adapted toact in compression and in tension to lock the back aga-inst swinging either frontward or backward.

The advantages of the invention as here outlined are best realized when all, of its features and4 instrumentalities are combined, but, useful embodiments may be produced involving less than the whole.

It will be obvious to those skilled in the art to which the invention appertains, that'the same may be incorporated in several different constructions. The accompanying drawing, therefore, is submitted merely as showing a preferred exemplication of the invention.

Referring inidetail'to the drawing. I' denotes a recliningchair exemplifyinga structure embodying the invention. The said chair may comprise a seat II of metal, composition or other suitable material carried by a frame including rear and front legs I2, I3, interconnected by cross ribs I4, the rear legs formingu'pwardly. extending standards I5 connected by the .armbars I6 to the front legs I3. A swingable back 'I1 for the chair may include any suitable frame comprising cross bars I'Ia and upright marginal tubular membersfIS. .Jn one lor both of said vmembers .isidisposed -a vcamfollower rod I9 slid- ;able :in ythe -tube Aalong :apathr-which may be vlengthened tir-'shortened (by Ia stop or cap 20 having threaded engagement `with .the -upper end portion of the tubular member I8.

Hinge fmeans .2I connects the tubular` member I8-With-the.-.trame-or-rear legs` I2-at any Vsuitableipointfpreferably.-adjacent to the yseat VI I. A bracket -2-2.y is bolted to the vframe at 23, this .bracket havinga .pair .ofaarmslll. Between the latter .is disposed Aa .disc 25 in ca-mming relation -to :the follower I8 as will be apparent hereinafter. vAlso-disposedbetween thearms 24and journaled-on -said-disc lisa cam ring element -2 carryingfa followerrhead 21. Formed at the lower end .of-the tubular-element .I8 .is a vbracket or pair fof arms `.28 spaced .to-.receive thearms .24. Interconnecting `the .disc element 25-With the armslifis -a `pin 29 rwhichfis free ofthe arms 2B. -A-...bolt .30 .passes through [arms .24, 28 and the ydisc -element v.Thus .the rbolt cooperates `with the 'pinl29,to-hold=the .disc element in fixed position, this .boltpivotally 'mountingv the tubular element ISYfor .hinging movement. 4Thearrangelment-ofthe -devicef-ZI .is-such that fora particular setting of the cap 20, counterclockwisemovement ofthe element I8. is. resisted because the rod- I9^actsfin Acompressionbetween the cap and the'head 21, this causing a stress on the cam ring 26 .concentric with the elementl,` :but eccentric ,to thepivotlboltu The .cammingcoaction .referred to-is obtained becausethe .axis lof, .the .alined elements. -I 9 .and 21..is eccentric tothepivot 3D.of :the fcam ring 28. -Accordinglythere is producedatriangleof forces of-which oneapexl-may be regarded as `located at 2U, another at the center of the bolt-:3Q and a third at the true center 3| of. the disc and ring .elements 25, 26, Counterclockwise.motionis -resisted,.sincelthe side;20,-.3I ofthe triangleis un- .der acompression resi-stedby the lrod I9, and the side 2D, 30 of the triangle is under'a tension resisted by the ,tubular element i8. Rreferably the location of the bolt or pivot 3D is aboveand front- 4wardof .theaxis 3| .while theiaxisof I3, 21 is rearWa-rdfof the.axis.30 thusgaffording a maximum range of adjustment forftheback -of the chair.- `gIhe back I1.is freeto swing V.frontward because while. the triangleside. 2U, '30 is of xed length, the other `sidedete-rmined bythe length o'f 4theelements I 9, 21 varies ,since these lelementsare free to separate and the elementv I9 is .free to separate from the cap 20. This is of advantage because the back can freelyv swing forwardly to follow a person who wishes to sit upright for a short while, and does not desire to change the stop adjustment for the back. 'I'he latter may be yieldingly urged forwardly, by a spring 32 that may in practice be encased in a tube of rubber or cloth. This spring may have a tension only suicient to impart a light support and to yield readily when the occupant of the chair returns to reclining position. However, this ;springmaybe omitted. In the drawing'it is shownstretched for convenience of illustration.

.For increased reclining, the cap 20 is merely upwardly .unscrewed slightly and for a. more up- 'right position the cap is downwardly screwed somewhat. A single turn may afford a substantial adjustment. There is no chance of the back l1'accidentally falling all the way rearward, as where a frictional thumbscrew was loosened. The back drops rearwardly only as the cap is unscrewed. And-where a person sits upright, the back may-be instantly moved .upright vand looked-by a spin ofthe capf20.

The invention may be embodied ina door check or stop to `prevent accidental closing of adoor, or to limit .orprevent opening of.a door, and Yit may be embodied in a linkage for transmitting power or yfor movably supporting an object such as a lamp or telephone, forinstance at the cap'20.

In Fig. 4 is shown a modication ofthe invention whereby a body such as the chair back I1 or other article can be angularly vadjustably moved to a required position and there locked against movement ineither direction. In this device 35, the bracket 22, disc`25 and ring 264 are the same as before, but for the tube- I8 and rod I9 there are substitutedtube 36 and rod 31, the latter being connected to the ring, the tube havying connected at-its upper end-'thebushings 38, 39 which areswiveled together at 40 by 'annularly interengaginglips. vThe bushing 38 vis connected to the tube by a threadlil while bushing39 is connected tothe rod 31 byIathread-IIL. Peripheral portions of both bushings are exposed for easy engagement andv individual turning. Normally, the bushing 38 is stationaryas by ymeans of va reasonably tight thread, while .bushing 39 is freely rotated to adjust the rod 31. Accordingly the rod 31 i-s subjected to compression whenas in .the chair IU, a-counterclockwise force is `exerted on the back I1, and to tension `when a clockwise force is exerted on ,the back I1. .Movement in either direction is thus resisted and .may be Aobtained only ,by turning thebushing .'39 inthe proper direction. When the rod 31 isrv subjected to -axial strain, as when under tension, the camming actionmay be such that a force results at a slight angle .to the rod. To .permit the desired deflection, the element 31,may. include a link 43 pivotally connected to the main-.part oft the .rod by a pin-44,this linkbeingsumcie'ntly narrow or tapered to have clearance with the wall of the tube. This clearance is suilicientlylarge to allow the necessary. angular .movement of the .link,. and the tube may laterally support the v-link atthe limits of its movement. In the chair Ifsuch link is unnecessary because.the,head.21.is separate .of the Yrod ISI and vmay have .the .necessary small clearance with the vtube I8.

The device 35 maybe readily transformedinto a device such as I0 .by merely freeing lthe .rod of its fixed engagement with.a relatively-.stationary ,part such. as,..the. bushing 39, and Linterposing an obstruction-to. aiordan end bearing suri'ace .for the rod. lThusLthe thread 42 maybe ofsufficient length to receive a plug 4'5. The latter maybe screwed in and the bushing 38 unscrewed until the rod releases bushing 39 and bears on the plug 45. Now only bushing 38 is turned for adjustment, bushing 39 moving therewith.

I claim:

1. A device including a supporting member, a movable member pivotally connected thereto, one of the members being hollow, a closure means having adjustable threaded engagement with the hollow member at an end thereof remote from the pivot, a disc-like means at the pivot, said disc-like means being secured to one of the members, a cam ring journaled on the disc-like means, a follower rod slidable in the hollow member and 'being pivotally connected to the cam ring, the hollow member being eccentrically connected to the disc-like means, the closure means including a plurality of interconnected elements, one of the elements being swiveled on the other and being connected to the follower rod at the adjacent end of the latter, whereby the follower rod is adapted to act both in compression and in tension to prevent relative angular movement between the members.

2. A device including a supporting member, a member pivotally connected thereto, one member being a, tube, a rod slidable in the tube, means at the pivot having camming coaction with the rod at one end thereof so that the rod constitutes a cam follower, the cam means including a disc xed on the other member, and a cam ring journaled on the disc and pivotally connected to the rod and being rotatable about an axis eccentrically related to the pivotal connection of the tubular member so that longitudinal movement of the rod occurs relative to the tubular member upon adjustable relative angular motion between the members, and adjusting means connected to the tubular member and connected to the rod at the other end of the latter to prevent the movement of the rod with the same acting in compression and in tension to thus prevent the said relative angular movement, the adjusting means including a rst element having threaded engagement with the tubular element, a second element swiveled on the first element and adapted for threaded engagement with the follower rod, and a third stop element for the rod adjustably engaged with the second element and adapted to separate the rod against threaded engagement with the second element.

JOSEPH WHITE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,744,258 Bitzenburger Jan. 2l, 1930 621,669 Hinds Mai'. 21, 1399 FOREIGN PATENTS Number Country Date 477,511 Great Britain 1937 

